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<p class="p1">1. Explain briefly three different measures of the quality of a command language. <span class="Apple-converted-space"> </span></p>
<p class="p2"><br></p>
<p class="p1">Consistency - The same terms always mean the same thing.</p>
<p class="p1">Naturalness - Intuitive design.<span class="Apple-converted-space">  </span>The commands make sense.</p>
<p class="p1">Reasonableness - Responses are helpful and polite instead of witty/rude. etc.</p>
<p class="p2"><br></p>
<p class="p1">2. Explain briefly three features of a command language that are important primarily<span class="Apple-converted-space"> </span></p>
<p class="p1">because of their usefulness in command files. <span class="Apple-converted-space"> </span></p>
<p class="p2"><br></p>
<p class="p1">Intelligent Terminal Handling</p>
<p class="p1">Immediate Commands</p>
<p class="p1">Help Facilities</p>
<p class="p1">Packaging of Commands into scripts etc.</p>
<p class="p2"><br></p>
<p class="p1">3. State one advantage to use of a RUN command in a command language. <span class="Apple-converted-space"> </span></p>
<p class="p2"><br></p>
<p class="p1">Any possible action can be embedded in a program which can then be invoked at the user's convenience.</p>
<p class="p2"><br></p>
<p class="p1">4. State one advantage to use of keyword arguments rather than positional<span class="Apple-converted-space"> </span></p>
<p class="p1">arguments. <span class="Apple-converted-space"> </span></p>
<p class="p2"><br></p>
<p class="p1">More variations are possible and each command can then be better documented if recorded in a log file.</p>
<p class="p2"><br></p>
<p class="p1">5. Why would it be important for a program to know whether it was invoked by a<span class="Apple-converted-space"> </span></p>
<p class="p1">terminal command or a command file? <span class="Apple-converted-space"> </span></p>
<p class="p2"><br></p>
<p class="p1">Error correction must be possible if the program called was invoked by a command file?</p>
<p class="p2"><br></p>
<p class="p1">6. What is the principal difference between submitting a batch job and running a<span class="Apple-converted-space"> </span></p>
<p class="p1">command file? <span class="Apple-converted-space"> </span></p>
<p class="p2"><br></p>
<p class="p1">A batch job requires no user input what-so-ever.</p>
<p class="p2"><br></p>
<p class="p1">7. Describe two desirable qualities of a command interface and illustrate each with a<span class="Apple-converted-space"> </span></p>
<p class="p1">specific example. <span class="Apple-converted-space"> </span></p>
<p class="p2"><br></p>
<p class="p1">Echoing?</p>
<p class="p1">Break character?</p>
<p class="p2"><br></p>
<p class="p1">8. List and describe briefly five characteristics of a command language that are<span class="Apple-converted-space"> </span></p>
<p class="p1">desirable primarily to support command files. <span class="Apple-converted-space"> </span></p>
<p class="p2"><br></p>
<p class="p1"><span class="Apple-converted-space">    </span>• accept arguments like standard commands, to be substituted in their text like<span class="Apple-converted-space"> </span></p>
<p class="p1">macro arguments.<span class="Apple-converted-space"> </span></p>
<p class="p1"><span class="Apple-converted-space">    </span>• allow command files to invoke other command files in a nested structure.<span class="Apple-converted-space"> </span></p>
<p class="p1"><span class="Apple-converted-space">    </span>• allow input to come from either the terminal or the command file.<span class="Apple-converted-space"> </span></p>
<p class="p1"><span class="Apple-converted-space">    </span>• allow optional display of the commands executed on the terminal, and optional<span class="Apple-converted-space"> </span></p>
<p class="p1">logging to a file or printer.<span class="Apple-converted-space"> </span></p>
<p class="p1"><span class="Apple-converted-space">    </span>• allow comments in command files for documentation purposes.<span class="Apple-converted-space"> </span></p>
<p class="p1"><span class="Apple-converted-space">    </span>• allow the user to intervene when an error is detected, and then resume the<span class="Apple-converted-space"> </span></p>
<p class="p1">command file at a suitable point. <span class="Apple-converted-space"> </span></p>
<p class="p2"><br></p>
<p class="p2"><br></p>
<p class="p1">9. List and briefly describe three possible criteria that you can use to evaluate the<span class="Apple-converted-space"> </span></p>
<p class="p1">quality of a command language. <span class="Apple-converted-space"> </span></p>
<p class="p2"><br></p>
<p class="p2"><br></p>
<p class="p2"><br></p>
<p class="p1">10. List three examples of common system calls unrelated to file management. <span class="Apple-converted-space"> </span></p>
<p class="p2"><br></p>
<p class="p3">time</p>
<p class="p3">who</p>
<p class="p3">exit or terminate</p>
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